1. Field of the Invention
The present invention relates to an audience rating measuring system.
2. Description of the Prior Art
To measure TV audience rating, there has previously been used a measuring instrument called a videometer, which records the time at which the power source of a television set is turned on or off, the channels viewed, and the like on a paper tape or memory device.
In recent years, however, video tape recorders for domestic use have been so widely used that it is becoming difficult to measure the audience rating with conventional audience rating measuring systems. That is to say, when the television set is simply used without accessory components, the content which the audience is viewing is a program which is being broadcast. Therefore, the condition of viewing can be correctly recorded relying simply upon the data related to turning on or off of the power source of the television set and the channel being viewed. With the television set being used in combination with a video tape recorder, however, there exists a variety of possibilities for viewing programs. For instance, the audience any record a program without really viewing the program at the time the program is being broadcast, and may view the program at a later time by playing back the recorded contents.
The measuring instrument (such as the videometer mentioned above) has the function of recording the data related to a television program that is being viewed in real time, but is not capable of obtaining data related to the use of video tape recorders.